Method of manufacturing a magnetic fuel or water treatment device

ABSTRACT

A method for manufacturing a device for the magnetic treatment of fluids including water, liquid and gaseous fuels, propane, oil and the like. An elongate inner tubular casing having a magnet therein is supported within an intermediate casing made of a ferromagnetic material, and a pair of end fittings are connected to opposite ends of the intermediate casing and serve to center the inner casing therein. The end fittings each have a tapered passage therein, and as they are threaded on the ends of the intermediate casing, the ends of the inner casing are guided into the tapered passages and are gradually deformed inwardly thereby so that the tapered passages tightly seat against the ends of the inner casing to prevent radial and axial movement of the inner casing relative to the end fittings. This results in a self adjusting support of the inner casing and avoids crimping or other deformation which may result if the end fittings are threaded too far.

CROSS-REFERENCE TO RELATED APPLICATION

This is a division of application Ser. No. 167,921, filed July 14, 1980,now U.S. Pat. No. 4,357,237, issued Nov. 2, 1982, which is acontinuation-in-part of application Ser. No. 098,294, filed Nov. 28,1979, now abandoned.

BACKGROUND OF THE INVENTION

The present invention relates to a device for the magnetic treatment ofwater or reduce the buildup of scale and also relates to a device forthe magnetic treatment of liquid and gaseous fuels, such as gasoline,gasahol, diesel fuel, propane, natural gas, oil and the like, in orderto improve the efficiency of combustion and reduce the production of airpollutants.

With the energy shortage reaching worldwide proportions, especially withrespect to petroleum-based fuels, the need to burn such fuelsefficiently has never been of greater importance. Since the automobileis perhaps the largest consumer of petroleum today, significantconservation of gasoline and diesel fuel could be realized if thecombustion process were more efficient, thereby enabling greaterdistances to be driven on a given quantity of fuel. Furthermore, airpollution has increased drastically in recent years due to the expandeduse of automobiles and trucks, and there are very significant pressuresbeing placed on industry by governments to produce vehicle engines whichemit very low levels of pollutants.

Fuel efficiency and pollution reduction are important, not only inconnection with vehicles, but also with heating and electricitygeneration plants which burn hydrocarbon fuels, such as oil, naturalgas, and propane.

Although there has been considerable effort to reduce air pollutantsfrom engines, furnaces, electricity generating installations, and thelike, the primary emphasis has been on treatment of the exhaust andstack emissions rather than on devising techniques to burn the fuel moreefficiently thereby inherently resulting in the emission of fewer wasteproducts. A beneficial result of more efficient combustion is that thefuel is burned more completely so that fewer hydrocarbon waste productsare emitted in the exhaust gases.

The device is useful in increasing the efficiency with which fuel iscombusted by treating the raw fuel with a magnetic field. In the case ofvehicles, this results in increased mileage, and in the case of heatingand energy conversion plants, greater thermal output can be realized fora given quantity of fuel.

The device is also useful for the magnetic treatment of water to reducethe buildup of scale in pipes, fittings and other devices and apparatusthrough which water flows. A problem which is quite prevalent in systemsand apparatus which use large quantities of water, such as boilers,dishwashers, ice machines, and the like, is that of scale buildup on thesurfaces which come into contact with the water. This problem isparticularly acute in areas where the water has a high mineral contentso that it is necessary for the water to be "conditioned" either bychemical action or by magnetic water treatment devices of the generaltype to which the present invention relates.

One such magnetic treatment device is disclosed in U.S. Letters PatentNos. 3,951,807, 4,050,426 and 4,153,559. Basically, such devicecomprises an elongated magnet having a multiplicity of longitudinallyspaced poles encased in a non-magnetic jacket and concentricallypositioned within a galvanized or black iron casing mode of a magneticmaterial, such as iron. The jacketed magnet may be centered by means ofa pair of stepped collars secured thereto which, in turn, are centeredby means of a pair of layered inserts. Alternatively, the jacketedmagnet may be centered by means of resilient, tapered sleeves, which arewedged between the jacket for the magnet and the galvanized casing.

Magnetic treatment devices generally of this type are well known andprevent corrosion and the buildup of scale by causing the calcium andother minerals present in hard water to form, instead, a loose slurrywhich can be removed easily from the system by blowdown or flushing. Inmany applications, such as furnace humidifiers, for example, it isimportant for the device to be contained within a fairly small housing,and for this reason, available space is at a premium. Furthermore, theeffectiveness with which the water is treated depends on the intensityof the magnetic field within the treatment chamber and the effectivelength of the chamber itself. Accordingly, it is desirable that thechamber be free of any obstructions which may occupy otherwise availabletreatment space, and for the water to be directed into and completelyoccupy the treatment chamber as quickly and in as short a distance aspossible after it enters the device.

A further consideration is that the strength of the magnetic fieldproduced by the magnet be confined solely to the annular treatmentchamber so that all of the available flux will be utilized. An importantfactor is ensuring this situation is to completely magnetically isolatethe magnet from the supporting structure and to complete the magneticcircuit by means of a ferrous casing which surrounds the magnet, andwhich is also magnetically insulated from the magnet.

In the aforementioned U.S. Pat. No. 4,153,559, the magnet structure isdisclosed as being centrally supported within the ferrous casing bymeans of a pair of non-magnetic, elastic sleeves compressed between andin frictional engagement with the magnet structure and the ferrouscasing at opposite ends thereof. Additionally the magnet is frictionallyretained within its jacket by a pair of plastic end caps which furtherinsulate the magnet and also serve to prevent water from coming intocontact with it thereby causing corrosion. The ends of the inner casingwere flared outwardly partially around the ends of the elastic sleevesso as to provide a positive-type lock intended to prevent axial movementbetween the inner casing and the sleeves.

Although the frictional engagement between the inner casing and plasticend caps and between the inner casing and the elastic sleeves serves tohold the structure in proper position in normal use, a severe jolt tothe unit, as by dropping it during shipping or installation, may causethe magnet to shift axially thereby partially or completely blocking oneset of the apertures. Obviously, this would prevent the proper flow ofwater or fuel through the device. Furthermore, it is possible for theinner casing and elastic sleeves to shift as a unit relative to theferrous casing, and this may also result in partial or complete blockageof one set of the apertures and/or cause the previously annulartreatment chamber to become distorted thereby reducing the effectivenesswith which the magnetic field treats the water or fuel. Axial shiftingof the magnet and the magnet-casing structure may also be caused by asevere water hammer occurring in the water supply system, when thedevice is being utilized as a water conditioner.

One embodiment constitutes an improvement to the devices disclosed abovein that the inner casing in which the magnet is encased has itsopposite, tubular ends received within recesses in the end fittings,which are dimensioned to provide a snug engagement and to positivelylock the inner casing against axial movement relative to the fittings.Since the inner casing is retained immobile relative to the endfittings, which are threadedly secured to the ferrous casing, theseelements are maintained in their proper spatial relationship regardlessof trauma to the device. This arrangement also provides for lesspressure drop because the liquid flows directly into the inner casingwith minimal turbulence.

Although receiving the tubular end of the inner casing within recessesin the end fittings positively locks the inner casing againstlongitudinal movement relative to the end fittings and ferrous casing,on some occasions, difficulty has been encountered in assembling theunit. If the end fittings are screwed on the ferrous casing past thepoint where the ends of the inner casing are contacted by the bottoms ofthe recesses in the end fittings, the inner casing will be axiallydeformed. If this occurs, it is possible that the inner casing couldbuckle outwardly thereby reducing the volume of the annular treatmentchamber, and even exposing the magnet to the flow of liquid if theliquid-tight seal between the inner casing and the end caps supportingthe magnet is disrupted.

As an alternative, the recess in each of the end fittings is replaced bya tapered passage, which has a minimum inner diameter less than theouter diameter of the inner casing, and its maximum inner diametergreater than the outer diameter of the inner casing. Thus, as the endcaps are screwed onto the ferrous casing, the tapered passages contactsthe ends of the inner casing and deform the ends radially inward to aslight degree. This causes the inner casing to seat uniformly on the endfittings and provides a tight seal between the inner casing and the endfittings. Furthermore, the inner casing is prevented from shiftingaxially because it is tightly compressed by the end fittings. It isgenerally desirable that the tapered passages continue beyond the axialouter ends of the inner casing so that any further axial shifting of theinner casing will be opposed as the ends thereof are further compressedby the tapered passages.

In order to prevent the magnet from shifting axially relative to theinner casing, portions of the tubular end portions of the inner casingare deformed inwardly so as to form locking projections which wouldengage the capped magnet and prevent it from moving axially. This,together with the seating arrangement for the inner casing, maintainsstructural integrity of the unit capable of withstanding severe joltssustained when dropped during shipping or due to a water hammer when thedevice is employed as a water conditioner. The structural arrangementaccording to the invention is also advantageous when the device is usedas a fuel treater in vehicles, because the repeated and sometimes severejolts to the engine as the vehicle traverses rough terrain may otherwiseresult in movement between the elements making up the device.

Specifically, the device comprises: an elongated, tubular intermediatecasing of magnetic materials; an elongated magnet having opposite endsand at least two axially spaced poles; an inner casing of non-magneticmaterial encasing the magnet and having open, tubular end portionsextending beyond opposite ends of the magnet; and a pair of end fittingsconnected to opposite ends of the intermediate casing and havingexternally open fluid passages therein. Each of the end fittingsincludes a recess spaced from and opening toward the magnet withrespectively opposite tubular end portions of the inner casing receivedtherein so as to radially space the inner casing from the intermediatecasing thereby forming an annular treatment chamber therebetween. Therecesses are in fluid communication with the fluid passages of therespective end fittings, and apertures are provided in each of thetubular end portions so as to form fluid flow paths from within thetubular end portions to the treatment chamber. An outer casing made ofcopper or other suitable material is received on turned down shoulderson the end fittings and is spaced outwardly from the intermediatecasing. This serves to prevent the intermediate casing from coming intocontact with other ferrous materials when the unit is installed.

In accordance with the invention, wherein the recesses are formed astapered passages which have a minimum inner diameter less than the outerdiameter of the inner casing ends, and a maximum inner diameter greaterthan the outer diameter of the inner casing ends, as the end fittingsare threadedly secured to the ferrous casing, the inner casing ends arepressed inwardly thereby forming a snug fit between the inner casing andend fittings. This prevents movement of the inner casing, both in theaxial and radial directions. A further advantage to this embodiment isthat the length of the inner and ferrous casings and the extent to whichthe end fittings are threaded onto the ferrous casing are much lesscritical. This is because the end fittings and inner casing are not inaxial abutment, but the end fittings can continue to slide over theinner casing as they are threaded onto the ferrous casing with the onlyeffect on the inner casing being that of a slight inward deformation.

The outer diameter of the inner casing, a dimension which is sometimesdifficult to maintain within tolerances, is also much less criticalbecause the ends of the inner casing are automatically sized as they aredeformed inwardly by the tapered passage. This relationship is alsoadvantageous from the standpoint of precisely centering the inner casingwithin the ferrous casing so as to provide an annular treatment chamberwhich is perfectly concentric relative to the magnetic field.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a longitudinal sectional view of the magnetic water and fueltreatment device according to one embodiment;

FIG. 2 is a transverse sectional view taken along line 2--2 of FIG. 1and viewed in the direction of the arrows;

FIG. 3 is a transverse sectional view taken along line 3--3 of FIG. 1and viewed in the direction of the arrows;

FIG. 4 is a transverse sectional view taken along line 4--4 of FIG. 1and viewed in the direction of the arrows;

FIG. 5 is an enlarged, fragmentary sectional view of one of the ends ofthe inner casing which has been inwardly deformed to prevent axialmovement of the magnet;

FIG. 6 is a sectional view taken along line 6--6 of FIG. 5 and viewed inthe direction of the arrows;

FIG. 7 is an exploded perspective view of the device;

FIG. 8 is a side elevational view showing the device mounted within thefuel line of a typical automobile internal combustion engine.

FIG. 9 is a side elevational view, partially in section, of the magnetand inner casing assembly showing crimping of the apertures;

FIG. 10 is a perspective view of the crimping tool;

FIG. 11 is a perspective view of the magnet and inner casing assemblywhich has been crimped as shown in FIG. 9; and

FIG. 12 is a fragmentary sectional view of one of the taperedpassageways.

DETAILED DESCRIPTION

Referring now to the drawings, the magnetic water and fuel treatmentdevice comprises an outer casing 10 made of a non-magnetic material,such as copper, and a pair of substantially identical fluid fittings 12and 14, also of a non-magnetic material, such as brass. Fittings 12 and14 are provided with flanges 16 and 18, respectively, which abutopposite ends 20 and 22 of outer casing 10. It will be seen that outercasing 10 is supported on annular shoulders 24 and 26 such that theouter surface 28 of casing 10 is substantially flush with the outersurfaces 30 and 32 of fittings 12 and 14, respectively.

Hexagonal heads 34 and 36 permit fittings 12 and 14 to be tightened bymeans of a standard wrench, and adapters 38 and 40 are provided withbarbed outer surfaces 42 and 44 to facilitate connection with flexiblehoses 46 and 48, which may comprise the fuel line of an internalcombustion engine, for example. Hoses 46 and 48 are clamped by hoseclamps 35. Depending on the particular application for the device, andfittings 12 and 14 may be provided with standard pipe threads forconnection to pipe, or compression fittings for connection to thinwalled copper pipe or tubing. The last two types of connections would beused when the device is serving as a water conditioner or for thetreatment of natural gas or oil in the case of a furnace or heatconversion plant. In the embodiment illustrated, which is particularlyadapted for connection in an engine fuel line, the barbed surfaces 42and 44 dig into the inner surfaces 50 and 52 of tubing 46 and 48 so asto resist disconnection while at the same time permitting easyattachment. Obviously, other types of fittings and connections may beutilized depending on the environment and intended use for the device.

For purposes of the present application, the term "non-magnetic" meansmaterials having a very low magnetic permeability and virtually noferromagnetic characteristics, such as copper, brass, PVC, nylon andDelrin, for example. "Magnetic" materials are those materials exhibitinghigh magnetic permeability, such as iron and certain steels.

A tubular intermediate casing 54 of a ferromagnetic material having ahigh magnetic permeability, such as galvanized iron or steel, isthreadedly connected to fittings 12 and 14 by threads 56 and 58. Ifdesired, threads 56 and 58 may be coated with pipe grease or wrappedwith Teflon tape to provide a water-tight seal between fittings 12 and14 and casing 54. Casing 54 has an outer diameter less than the innerdiameter of outer casing 10 to form an annular space 60 therebetween.

Positioned within intermediate casing 54 is a tubular inner casing 62 ofa non-magnetic material, such as copper, which is open at both ends 64and 66. Inner casing 62 is received within recesses 68 and 70 infittings 12 and 14, respectively, which open toward the center of thedevice and are in fluid communication with passages 72 and 74. Innercasing 62, fittings 12 and 14 and intermediate casing 54 are dimensionedsuch that, when fittings 12 and 14 are screwed tightly onto intermediatecasing 54, the axial edges 76 and 78 of inner casing 62 abut the bottoms80 and 82 of recesses 68 and 70, respectively. Recesses 68 and 70 arepreferably dimensioned such that the ends 64 and 66 of inner casing 62will be snugly received therein when the device is assembled. Taperingwalls 84 and 86 on fittings 12 and 14, respectively, assist in guidingthe ends 64 and 66 of inner casing 62 into recesses 68 and 70.

The particular arrangement shown in FIG. 1 causes the liquid to flowdirectly from passage 72 into inner casing 62 without first flowing intoan enlarged chamber, as in the case of certain prior art waterconditioners. When liquid flows into an enlarged chamber, the laminarflow pattern is disrupted and turbulence occurs. This results in agreater pressure drop, which reduces efficiency and may require the useof a larger capacity unit. By causing the liquid to flow directly intoinner casing 62, laminar flow is generally maintained and loss ofpressure is minimized. Also mixing of the liquid with air is reduced.

Retained within inner casing 62 is an elongated permanent magnet 88,preferably having a composition of cobalt, nickel, aluminum, copper andiron, and is magnetized along its longitudinal axis to have a pluralityof longitudinally spaced-apart poles of alternate North and Southpolarity represented by the symbols "N" and "S". Magnet 88 issubstantially homogeneous in composition and, in the embodimentillustrated, comprises two magnetic domains extending transverselythroughout the magnet and having their magnet moments oppositely alignedsuch that opposite North and South poles exist along the length of themagnet. A magnet such as this may be produced by imposing on a bar ofmagnetic material two longitudinally displaced static magnetic fields ofopposite polarity. The number of poles for a particular magnet dependsto a great extent on the size of the device and on the intended flowrate capacity, so that in the case of a very small capacity device, amagnet having only two poles may be the most efficient. It is preferablethat magnet 88 be made of a material having a high energy product andhigh retentivity and coercivity, such as an Alnico material. Withinthese desirable constraints, a wide variety of commercially availablemagnets and magnetic materials may be utilized.

Magnet 88 is provided with a pair of resilient end caps 90 and 92, whichare received over the opposite ends thereof and compressed between itand the inner surface 94 of inner casing 62 so as to frictionally retainthe magnet 88 in place. When the device is used as a water conditioner,caps 90 and 92 are preferably made of polythylene, and if the device isused as a fuel treater, they are made of brass. In both cases, the caps90 and 92 are made of a non-magnetic material so as to magneticallyinsulate the magnet 88 from the rest of the device. End caps 90 and 92also serve to space the magnet 88 from the inner surface 94 of the innercasing 62.

Inner casing 62 is centered within intermediate casing 54 so as to forman annular treatment chamber 96 defined by the inner surface 98 ofintermediate casing 54 and the outer surface 100 of inner casing 62. Inorder to permit fluid flow between the interiors of the tubular endportions 64 and 66 of inner casing 62 and the annular treatment chamber96, apertures 102 and 104 are cut in the tubular end portions 64 and 66,respectively. Apertures 102 and 104 are displaced 180° from each otherabout the longitudinal axis of the device so that the water or fuelwhich enters the treatment chamber 96 through one of the apertures willbe caused to make a 180° revolution about the axis within chamber 96before flowing out of the opposite aperture. This allows more of thechamber 96 to be utilized, because otherwise, a portion of the treatmentchamber 96 would receive little or no fluid flow. Depending on the flowcapacity of the device, additional apertures (not shown) may be cut inthe tubular end portions 64 and 66, and if only two additional aperturesare so provided, they are preferably aligned diametrally opposite theexisting apertures 102 and 104, but apertures 102 and 104 would then bedisplaced 90° from each other rather than 180°. In most cases, it isdesirable that the cross-sectional areas of the passages 72 and 74,apertures 102 and 104, and chamber 96 be selected so as to maintain thepressure drop at a low level for the rated flow capacity of the device.

Although the frictional forces between the plastic or brass end caps 90,92 and the inner surface 94 of inner casing 62 are generally adequate toprevent axial shifting of the magnet and end cap assembly during normaluse, dropping the device on its end during shipping or installation mayresult in blockage of one of the apertures 102 and 104. This is causedby the magnet and end cap assembly shifting axially over one of theapertures 102 or 104, thereby either completely blocking orsubstantially reducing the rate of flow through the obstructed aperture102 or 104 so that the throughput of the device is substantiallylowered. In the case where the device is used as a water conditioner,this may result in unacceptable losses in line pressure, and in the casewhere the device is used as a fuel treater, stalling of the engine dueto inadequate supply of fuel to the carburetor or fuel injectors is apossibility.

In order to positively lock the magnet and end cap structure within theinner casing 62, the tubular end portions 64 and 66 of inner casing 62are crimped inwardly at points 106 and 108 (FIGS. 5 and 6) in the areaof the edges 110 and 112 of apertures 102 and 104 (FIGS. 5, 6 and 7).Preferably, the crimped portions are located in the areas indicated bynumeral 114 which is the inside corner nearest the magnet 88.

The crimped portions 106 and 108 form inwardly projecting lockingprotrusions 116 that prevent the end caps 90 and 92 from shifting pastthe crimped portions 106 and 108 just inside the apertures 102 and 104.

The structure described above is designed to concentrate the magneticfiled produced by magnet 88 in the annular chamber 96 immediatelyadjacent thereto and at the same time insulate this field from thesupporting structure. Due to the high permeability of intermediatecasing 54, the flux produced by magnet 88 will extend radially outwardtherefrom, flowing within intermediate casing 54, and then return tomagnet 88 without straying from the treatment chamber 96. By thuscontaining the magnetic field, maximum efficiency in subjecting thewater or fuel flowing through the device to the magnetic field isachieved. Containment of the magnetic field is further enhanced throughthe use of non-magnetic materials for the outer casing 10, fittings 12and 14, inner casing 62 and plastic or brass end caps 90 and 92.

The device is assembled by first inserting the magnet 88 within innercasing 62 and then pressing the brass end caps 90 and 92 over the endsof the magnet 88 so that they are compressed between the magnet 88 andthe inner surface of inner casing 62. If plastic end caps 90 and 92 areutilized, however, they are first placed over the ends of the magnet 88,and then this assembly is pressed into the inner casing 62. After themagnet 88 and end caps 90 and 92 are in place, the tubular end portions64 and 66 are crimped as illustrated in FIGS. 5 and 6.

Inner casing 62 is then inserted within the recess 70 of fitting 14, andintermediate casing 54 is loosely screwed into fitting 14. The outercasing 10 is then slipped over intermediate casing 54 and guided ontoannular shoulder 26. The other fitting 12 is screwed onto the other endof intermediate casing 54 and, as mentioned earlier, the tapered surface84 of fitting 12 assists in guiding the end 64 of inner casing 62 intorecess 68. Fittings 12 and 14 are then tightly screwed onto intermediatecasing 54 until the ends 76 and 78 bottom out against the axial surfaces80 and 82 of recesses 68 and 70. Outer casing 10 is preferablydimensioned so that it will fit snugly between shoulders 24 and 26 offittings 12 and 14 when fittings 12 and 14 are tight. The threadedportions 56 and 58 of intermediate casing 54 are preferably taperedslightly so that as fittings 12 and 14 are screwed thereon, afluid-tight seal is achieved.

FIG. 8 illustrates the manner in which the above-described device may bemounted within the gasoline-fuel engine 118 of an automobile. The fueltreatment device, which is indicated generally by the numeral 120, ispreferably connected in the fuel line, which has been severed so as toform portions 46 and 48, as close to the inlet of the carburetor 124 aspossible. Thus, as the fuel is pumped from the gasoline reservoir (notshown) by fuel pump 126, it will flow through fuel line 46, passage 72,tubular end portion 64, aperture 102, annular treatment chamber 96,aperture 104, tubular end portion 66, passage 74, and fuel line portion48 into carburetor 124. As the fuel flows through the annular chamber96, it is subjected to the high density, substantially radial magneticfield produced by magnet 88. Although the effect of the magnetic fieldon the fuel is not fully understood, it is believed that this treatmentcauses the vaporized fuel to disperse more rapidly once it enters theexpanded area of the combustion chamber thereby causing more completecombustion resulting in greater fuel efficiency and performance and areduction of exhaust emissions.

Although not illustrated, the device 120 may also be used in conjunctionwith a diesel engine by connecting it in the fuel line prior to the fuelfilter and the fuel injectors. Furthermore, the device may be used fortreating propane, both in vehicles and other installations, as well asnatural gas and oil, such as in furnace installations and electricitygenerating plants. In each case, it is important that the fuel betreated prior to its reaching the air/fuel mixing apparatus, such as thecarburetor, fuel injector, nozzle, burner, etc.

As indicated earlier, the device is useful for conditioning or treatingwater, in which case it is series connected directly in the water supplyline, prior to the boiler, humidifier, ice maker, or other apparatuswherein scale is a problem.

The water and fuel treatment device has been shown and described ashaving an overall shape which is generally symmetrical about a straightaxis, but other configurations are not excluded. Although aNorth-South-South-North arrangement for the poles of magnet 88 have beenillustrated in connection with the preferred embodiment, otherarrangements, such as South-North-North-South will also be effective.Furthermore, the number of poles can be increased or decreased dependingon the space and flow capacity requirements of the device.

FIGS. 9-11 illustrate an alternative technique for locking the magnetand end cap assembly against axial movement within inner casing 62.Similarly to copending U.S. Pat. No. application Ser. No. 121,646 filedFeb. 14, 1980 now U.S. Pat. No. 4,299,700 in the name of Charles H.Sanderson, apertures 102 and 104 may be crimped by means of a tool 130,which is inserted in the apertures as shown in FIG. 9 and pivoteddownwardly so as to bend edge 132 of aperture 102 upwardly and bend edge134 downwardly at angles of 45° relative to the longitudinal axis. Edges136 and 138 of aperture 104 are similarly deformed.

Inwardly deformed edges 134 and 138 form locking protrusions on theinner surface 94 of inner casing 62 so as to prevent magnet 88 and endcaps 90 and 92 from shifting axially. An additional advantage to thisconfiguration is that apertures 102 and 104 are shaped such that theyform deflector surfaces which tend to scoop the incoming water or fuelinto annular chamber 96, and then scoop the fuel or water out of chamber96 toward outlet end 66. This provides an easier flow path for theliquid and, therefore, produces less pressure drop than in the casewhere the liquid must make a right angle turn before it begins to flowin chamber 96 and then another right angle turn as it leaves chamber 96.

FIG. 10 illustrates the crimping device 130 which is used to deformapertures 102 and 104. It comprises a handle 141 adapted to be grippedby the person crimping apertures 102 and 104, and a tool portion 143having an upper surface 147, which has the same curvature as the inneredge of apertures 102 and 104 when tool 130 is inserted into apertures102 and 104. If desired the lower surface of portion 143 may tapergradually into a concave surface toward handle 141, as shown in FIG. 10.

As discussed earlier, one of the problems with the embodimentillustrated in FIG. 1 is that tightening of the end fittings 12 and 14onto intermediate casing 54 is critical because it is desirable that thesurfaces 80 and 82 of recesses 68 and 70 just bottom out against theends 76 and 78 of inner casing 62. If end fittings 12 and 14 aretightened too far on intermediate casing 54, as may be the case if outercasing 10 is too short, inner casing 62 may be buckled at the aperturesthereby allowing the inner casing 62 to come in direct contact with theintermediate casing 54. This would cause a partial obstruction in theannular treatment chamber 96, and would result in a reduction inefficiency of the device. Additionally, inner casing 62 may pull awayfrom end caps 90 and 92 thereby exposing the magnet 88 to the liquid. Afurther difficulty with the embodiment of FIG. 1, is the necessity tohave the outer diameter of inner casing 62 be within very closetolerances so that it will not rattle within end fittings 12 and 14.

FIG. 12 illustrates one end of a fuel treater or water conditionermanufactured according to the present invention wherein the ferrouscasing and magnet structure have been removed for the sake of clarity.The opposite end structure is identical.

Inner casing 142, within which the magnet (not shown) is supported byend caps (not shown) similarly to the embodiment of FIG. 1, is directlysupported by the end fittings 140 so that it is concentrically disposedwithin the outer casing (not shown). It should be noted that the outercasing, intermediate casing and magnet structure associated with theembodiment of FIG. 12 are identical to that of FIG. 1. End fittings 140includes a tapered passage 156 which has a generally uniformlydecreasing diameter in the axial direction away from the magnet. Thus,as end fittings 140 are threaded onto the ferrous casing by means ofthreads 152 within portion 150, the ends 158 of inner casing 142 will bedeformed radially inwardly as illustrated in FIG. 12. This provides avery snug fit between the outer surface 157 of inner casing 142 andtapered passages 156 so that movement in the radial direction as well asthe axial direction is prevented. It will be seen that any axialmovement of inner casing 142 relative to end fittings 140 will beresisted because of the compression between inner casing 142 and thetapered passages 156.

Assume, for example, that the outer casing which is supported on annularsteps 153 is cut slightly shorter than its optimum length. This willresult in end fittings 140 being screwed on the intermediate casing to agreater extent than necessary before the ends of the outer casing bottomagainst end fittings 140. This presents no problem relative to innercasing 142, however, because it continues to be deformed inwardly sothat a tight fit between it and tapered passages 156 will exist at alltimes. No buckling of inner casing 142 occurs because relative slidingmovement between passages 156 and the outer surface 157 of inner casing142 occurs. In fact, end fittings 140 could even be tightened down tothe extent that inner casing 142 would protrude beyond tapered passages156 into the area defined by tapered surface 154, although this isgenerally not desirable.

In order to permit inner casing 142 to be easily inserted within taperedpassages 156, the larger diameter ends thereof are preferably largerthan the outer diameter of inner casing 142. It is necessary that theminimum inner diameter at the axially outer ends of tapered passages 156be smaller than the outer diameter of the ends 158 of inner casing 142so that the desired tight fit is achieved. End fitting 140 is providedwith a hexagonal portion 148 to permit the end fitting 140 to be screwedonto the intermediate casing. Portion 144 is provided with internalthreads 146 for attachment to a standard threaded pipe. Alternatively,the embodiment of FIG. 12 could be configured for attachment to fuelline hose, a compression fitting, or any other liquid conveying meansdepending on its intended use.

The embodiment of FIG. 12 is assembled by first inserting the magnet 88within inner casing 142 and then pressing the brass end caps 90 and 92over the ends of the magnet 88 so that they are compressed between themagnet 88 and the inner surface of inner casing 142. If plastic end capsare utilized, however, they are first placed over the ends of magnet 88,and then this assembly is pressed into inner casing 142. After themagnet 88 and end caps 90 and 92 are in place, the tubular end portionsare crimped as illustrated in FIG. 5 in the case of the previousembodiment.

Inner casing 142 is then inserted within the tapered passage 156 of oneof the end fittings 140, and the intermediate casing is loosely screwedinto threads 152. The outer casing 10 is then slipped over theintermediate casing and guided onto annular shoulder 153. The otherfitting 140 is screwed onto the other end of intermediate casing 54, andis guided onto inner casing 142 by virtue of the fact that the maximumouter diameter of tapered passage 156 is slightly larger than the outerdiameter of inner casing 142. Fittings 140 are then tightly screwed ontothe intermediate casing 54, and as tapered passages 156 are pressed overthe ends 158 of inner casing 142, the ends 158 are deformed inwardly bythe radial inward tapering forces as illustrated in FIG. 12. Endfittings 140 are screwed onto intermediate casing 54 until the flangeportions 150 thereof abut the ends of outer casing 10.

While this invention has been described as having a preferred design, itwill be understood that it is capable of further modification. Thisapplication is, therefore, intended to cover any variations, uses, oradaptations of the invention following the general principles thereofand including such departures from the present disclosure as come withinknown or customary practice in the art to which this invention pertainsand fall within the limits of the appended claims.

What is claimed is:
 1. A method of manufacturing a magnetic water orfuel treatment device comprising:providing an elongate bar magnet,providing a tubular inner casing of non-magnetic material havingopposite end portions with apertures therein, and inserting the magnetin the inner casing such that the magnet is captured therein betweensaid apertures and held against axial movement relative to the innercasing, providing a tubular intermediate casing made of ferromagneticmaterial having ends and an inner diameter greater than the outerdiameter of the inner casing, providing a pair of end fittings eachhaving a gradually tapered passage therein wherein the tapered passageshave respective maximum inner diameters greater than the outer diametersof the ends of the inner casing and minimum inner diameters less thanthe outer diameters of the ends of the inner casing, and threading thefittings on the ends of the intermediate casing and guiding the ends ofthe inner casing into the tapered passages thereby causing the ends ofthe inner casing to be deformed gradually inwardly by the taperedpassages as the end fittings are threaded on the intermediate casing,the tapered passages tightly seating against the ends of the innercasing to prevent radial and axial movement of the inner casing relativeto the end fittings.
 2. The method of claim 1 including the step ofplacing a tubular outer casing around the intermediate casing andtightening the end fittings against the outer casing as they arethreaded on the intermediate casing.